title: Study on a linear relationship between limited pressure difference and coil current of on/off valve and its influential factors.
abstract: On/off solenoid valves with PWM control are widely used in all types of vehicle electro-hydraulic control systems respecting to their desirable properties of reliable, low cost and fast acting. However, it can hardly achieve a linear hydraulic modulation by using on/off valves mainly due to the nonlinear behaviors of valve dynamics and fluid, which affects the control accuracy significantly. In this paper, a linear relationship between limited pressure difference and coil current of an on/off valve in its critical closed state is proposed and illustrated, which has a great potential to be applied to improve hydraulic control performance. The hydraulic braking system of case study is modeled. The linear correspondence between limited pressure difference and coil current of the inlet valve is simulated and further verified experimentally. Based on validated simulation models, the impacts of key parameters are researched. The limited pressure difference affected by environmental temperatures is experimentally studied, and the amended linear relation is given according to the test data.
authors.affiliation: State Key Laboratory of Automotive Safety and Energy, Department of Automotive Engineering, Tsinghua University, Beijing 100084, People's Republic of China. Electronic address: jzhzhang@mail.tsinghua.edu.cn.
authors.forename: Junzhi
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Automotive Safety and Energy, Department of Automotive Engineering, Tsinghua University, Beijing 100084, People's Republic of China. Electronic address: henrylvchen@163.com.
authors.forename: Chen
authors.initials: C
authors.lastname: Lv
authors.affiliation: State Key Laboratory of Automotive Safety and Energy, Department of Automotive Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Yue
authors.affiliation: State Key Laboratory of Automotive Safety and Energy, Department of Automotive Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
authors.forename: Yutong
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Automotive Safety and Energy, Department of Automotive Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Yuan
keywords: Hydraulic modulation; Influential parameters; Linear relationship; On/off valves; Pressure difference limiting